Roma announced on Wednesday that it had agreed to sell the Argentina international to Tottenham for 30 million euros ($40 million), with the fee potentially rising by 5 million euros ($7 million) depending on his success at the London club.

Lamela joined Roma two years ago and while he excelled at times in front of goal, he had to endure two rocky seasons marked by multiple coaching changes and changing styles of play.

"Perhaps I wasn't able to do everything that I could have and would have wanted to, although it's also true that in terms of the squad we lacked something," Lamela said, speaking to reporters at an airport in Rome before boarding a flight to London.

Tottenham first broke its transfer record in July to sign Brazil midfielder Paulinho from Corinthians for 20 million euros (then $26 million).

That fee was eclipsed by Tottenham meeting the 30 million euros ($40 million) release clause to sign Spain striker Roberto Soldado from Valencia.

France defensive midfielder Etienne Capoue has also signed for around 11 million euros ($15 million) from Toulouse, and winger Nacer Chadli arrived for around 8 million euros ($11 million) from FC Twente.

Tottenham's spending is just short of 100 million euros ($133 million), the amount Real Madrid could pay to bring Gareth Bale from White Hart Lane in a world-record transfer that is being negotiated.